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Full-Text Articles in Physical Sciences and Mathematics
Soluble Acidic Species In Air And Snow At Summit, Greenland, Jack E. Dibb, R. Talbot, M H. Bergin
Soluble Acidic Species In Air And Snow At Summit, Greenland, Jack E. Dibb, R. Talbot, M H. Bergin
Earth Sciences
Simultaneous measurements of the concentrations of soluble acidic species in the gas, aerosol and snow phases at Summit, Greenland were made during summer 1993. Mean concentrations of gas phase HCOOH, CH3COOH, and HNO3 (49±28, 32±17 and 0.9±0.6 nmol m−3 STP, respectively) exceeded the concentrations of aerosol-associated HCOO−, CH3COO−, and NO3−by 1–3 orders of magnitude. On average, SO2 concentrations (0.9±0.6 nmol m−3 STP) were approximately 1/3 those of aerosol SO4=, but this ratio varied widely due largely to changes in the concentration of …
Estimation Of Stratospheric Input To The Arctic Troposphere: 7be And 10be In Aerosols At Alert, Canada, Jack E. Dibb, David Meeker, R C. Finkel, J Southon, Marc W. Caffee, Leonard A. Barrie
Estimation Of Stratospheric Input To The Arctic Troposphere: 7be And 10be In Aerosols At Alert, Canada, Jack E. Dibb, David Meeker, R C. Finkel, J Southon, Marc W. Caffee, Leonard A. Barrie
Earth Sciences
Concentrations of 7Be and 210Pb in 2 years of weekly high-volume aerosol samples collected at Alert, Northwest Territories, Canada, showed pronounced seasonal variations. We observed a broad winter peak in 210Pb concentration and a spring peak in 7Be. These peaks were similar in magnitude and duration to previously reported results for a number of stations in the Arctic Basin. Beryllium 10 concentrations (determined only during the first year of this study) were well correlated with those of 7Be; the atom ratio 10Be/7Be was nearly constant at 2.2 throughout the year. This relatively high value of 10Be/7Be indicates that the stratosphere …
Sulfate And Msa In The Air And Snow On The Greenland Ice Sheet, J L. Jaffrezo, C Davidson, M Legrand, Jack E. Dibb
Sulfate And Msa In The Air And Snow On The Greenland Ice Sheet, J L. Jaffrezo, C Davidson, M Legrand, Jack E. Dibb
Earth Sciences
Sulfate and methanesulfonic acid (MSA) concentrations in aerosol, surface snow, and snowpit samples have been measured at two sites on the Greenland Ice Sheet. Seasonal variations of the concentrations observed for these chemical species in the atmosphere are reproduced in the surface snow and preserved in the snowpit sequence. The amplitude of the variations over a year are smaller in the snow than in the air, but the ratios of the concentrations are comparable. The seasonal variations for sulfate are different at the altitude of the Ice Sheet compared to those observed at sea level, with low concentrations in winter …
137cs Gamma-Ray Detection At Summit, Greenland, P. P. Dunphy, Jack E. Dibb
137cs Gamma-Ray Detection At Summit, Greenland, P. P. Dunphy, Jack E. Dibb
Earth Sciences
Global fall-out from atmospheric testing of thermonuclear weapons produced horizon markers corresponding to the initiation of testing in 1953 and the maximum fall-out in 1963. The radioactive isotope 137Cs associated with these events has a half-life of 30.2 years. Therefore, with the appropriate radiation detectors, this fall-out can be used as a long-term temporal indicator in glaciers and snowpack. A prototype γ-ray detector system was successfully tested and was used to make in-situ measurements of the 137Cs marker in a borehole at Summit, Greenland. The system consisted of a 7.6 cm by 7.6 cm NaI (Tl) scintillation crystal/photomultiplier detector, commercial …
An Ice-Core-Based Record Of Biomass Burning In The Arctic And Subarctic, 1750-1980, Sallie I. Whitlow, Paul A. Mayewski, Jack E. Dibb, Mark S. Twickler, G Holdsworth
An Ice-Core-Based Record Of Biomass Burning In The Arctic And Subarctic, 1750-1980, Sallie I. Whitlow, Paul A. Mayewski, Jack E. Dibb, Mark S. Twickler, G Holdsworth
Earth Sciences
No abstract provided.